1. Field of the Invention
The present invention relates generally to building information models (BIMs), and in particular, to a method, apparatus, and article of manufacture for automatically creating an accurate and reliable energy analytical model (EAM) from any combination of BIM elements, and for representing the EAM in BIM form so that it can be viewed, queried, and checked against the physical model.
2. Description of the Related Art
Three-dimensional (3D) Building Information Models (BIMs) today essentially comprise two key methods or objects used for defining and representing physical architectural building form: Conceptual Massing Elements (CMEs), and Architectural Building Elements (ABEs).
CMEs can be defined as being simple abstract representations of building mass, volume and surfaces comprising a single composite 3D solid, where all individual surfaces that form the boundary of the CME have zero thickness. These are typically used in the early stages of architectural design and for simple representation of surroundings buildings and other context. ABEs on the other hand can be defined as detailed representations of the individual physical components that a building comprises i.e. walls, floors, roofs, windows, ceilings, curtain panels etc. Unlike CMEs, ABEs represent the thickness as well as layers and other characteristics that describe the detailed physical and geometric form of the architectural elements. FIG. 1A illustrates a single CME type object and FIG. 1B illustrates multiple CMEs representing a whole building. Similarly, FIG. 2A illustrates example architectural building element (ABE) type objects, while FIG. 2B illustrates multiple ABEs representing a whole building.
In practice, as the architectural design process moves from concept to detail, these two elements are used in a virtually infinite number of ways to represent architectural building forms. FIG. 3 illustrates CME and ABE modeling from concept to detailed design (e.g., from CME model 302 to the ABE model 304, to the detailed resulting model 306). In addition to this complexity, the accuracy and completeness of BIM modeling can vary widely with the models, typically containing small inaccuracies between elements in the form of gaps, overlaps, and even omissions of elements in certain areas. FIG. 4 illustrates examples of typical architectural modeling inaccuracies and omissions (e.g., overlap 402, gap 404, omissions 406, etc.).
Energy Analytical Models (EAMs) on the other hand essentially comprise Spaces and Surfaces, where each Space represents a discrete volume of air inside a building (an office, atrium, hallway, living room, bedroom, etc.) and each Surface represents a path of heat transfer between two Spaces, or between a Space and the exterior environment. The critical aspects of an EAM that determine its accuracy or reliability are a suitable level of discretization (often referred to as thermal zoning) and the representation of each heat transfer surface's area, orientation and tilt. To date, while there are numerous methods for the creation of an Energy Analytical Model from a BIM, all of these impose severe restrictions on what elements the BIM comprises, on how they are combined and configured together, and on the accuracy and completeness of the BIM model.
Finally, to date there has never been a way to represent the EAM elements in BIM form—either only some simplified version of the EAM can be seen, or the EAM must be viewed in a 3rd-party application.